Democrats and Republicans on the Senate Finance Committee are at odds over how far to go in preventing insurance companies from covering the procedure for woman who would get subsidies.

WASHINGTON — As the Senate Finance Committee continued to debate its version of a healthcare overhaul bill Wednesday, Democrats and Republicans clashed over abortion -- potentially complicating President Obama's drive for action this fall.

At issue is how far healthcare legislation should go to prevent insurance companies from offering abortion services to the millions of women who could get taxpayer subsidies to help them pay premiums.

Federal funding of abortion has been prohibited since 1976, when an amendment by Rep. Henry J. Hyde (R-Ill.) banned Medicaid from paying for the procedure except in cases of rape, incest or medical necessity.

The bill now before the committee contains provisions that Democrats say would keep federal subsidy dollars from going to cover abortions. Republicans, however, say that the provisions are not strong enough. But an attempt to toughen them went down to defeat, and the confrontation threatened to further inflame debate over the issue.

Senate Democratic leaders are pushing to get a healthcare bill to the floor before the end of October, an imperative underscored Wednesday by Majority Leader Harry Reid (D-Nev.), who announced that he would cancel the chamber's traditional Columbus Day recess.

Reid is waiting for the finance committee to finish its version of an overhaul before hammering out a final bill for consideration by the full Senate. The committee, headed by Sen. Max Baucus (D-Mont.), is in its second week of debate on the measure. Baucus has said that he wants to finish up this week, although it is not clear whether that deadline can be met.

The federal government has policies against subsidizing abortion in most of its existing healthcare programs. The Tricare insurance program for members of the military does not cover abortion. Nor can private insurers who offer plans to federal employees through the Federal Employees Health Benefits Program cover the procedure.

Under the major Democratic proposals being debated on Capitol Hill, millions of Americans with low to moderate incomes could buy their insurance in a new, highly regulated marketplace in which private insurers would offer a variety of health plans.

Many of those people would qualify for federal aid to defray the cost of at least part of their premiums. And since many commercial insurers now offer abortion services as part of their package of benefits, it is likely that many of the plans in these marketplaces also would include abortion benefits.

That has stoked charges from antiabortion activists and their supporters on Capitol Hill that taxpayer dollars would be used to pay for abortions.

Senior House and Senate Democrats have sought to allay that concern by requiring insurance companies to divide the premiums they receive from policyholders and from the government to ensure that only money from policyholders be used for abortion services.

But that proposal has not assuaged antiabortion critics.

On Wednesday in the finance committee, Sen. Orrin G. Hatch (R-Utah) tried to prohibit the use of taxpayer money to pay for any part of an insurance plan that covers abortion services.

"All I am asking . . . is for specific language in the bill that prohibits federal dollars being used for abortion," Hatch told his colleagues. He suggested that women receiving subsidies would be able to buy supplemental plans with their own money to cover abortions.

But Democrats on the committee rejected Hatch's proposal, charging that it would amount to a new restriction on women's health services.

"It is a major, major change and a poison pill," said Sen. Maria Cantwell (D-Wash.).

Democrats voted down Hatch's proposal, 13 to 10, with Maine Sen. Olympia J. Snowe crossing the aisle to oppose Hatch. Democrats are counting on Snowe, a moderate Republican, to back their healthcare legislation. Sen. Kent Conrad of North Dakota was the only Democrat to vote for Hatch's proposal.

In the House, a group of socially conservative Democrats -- led by Rep. Bart Stupak of Michigan -- is pressuring party leaders to further tighten restrictions on abortion services in that chamber's healthcare bill, charging that the current provisions to have insurance companies segregate funds are inadequate.

"It doesn't fly with us," said Stupak, who met Tuesday with House Energy and Commerce Committee Chairman Henry A. Waxman (D-Beverly Hills), a leading architect of the House healthcare bill.

Stupak, who has pushed a version of Hatch's proposal, said that Waxman told him he was working on a possible compromise.